pages_before_pager

Description

Part of a system threshold
that immediately frees pages after an I/O completes instead of storing the
pages for possible reuse. The threshold is lotsfree + pages_before_pager. The NFS environment also uses this threshold to curtail its asynchronous
activities as memory pressure mounts.

Data Type

Signed integer

Default

200

Range

1 to amount of physical memory

Units

Pages

Dynamic?

No

Validation

None

When to Change

When the majority
of I/O is done for pages that are truly read or written once and never referenced
again. Setting this variable to a larger amount of memory keeps adding pages
to the free list.

When the system is subject to bursts of severe memory pressure. A larger
value here helps to keep a bigger cushion against the pressure.